Sony PMC-D305, Руководство по обслуживанию

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– 32 –
The following is a simple adjustment method.
– Simple Adjustment –
Note: Since exact adjustment cannot be performed, remember the posi-
tions of the controls before performing the adjustment. If the posi-
tions after the primary adjustment are only a little different, return
the controls to the original position.
+
–
TP (FOCUS-Y)
TP (TRACKING-Y)
TP (VC)
oscillosope
(DC range)
CD board
Procedure:
1. Keep the set horizontal.
If the set is not horizontal, this adjustment cannot be performed
due to the gravity against the 2-axis device.
2. Connect the oscilloscope TP (FOCUS-Y) and TP (VC) on the
CD board.
3. Insert the disc (YEDS-18) in and close the lid for CD.
4. Put the set into test mode. (See page 30.)
5. Press the
(
button.
From focus searching, focus is turned ON while entering
CLV drawing-in mode. Tracking and sled are turned OFF.
6. Press the
(
button.
[Both tracking and sled are turned ON.]
7. Adjust RV702 so that the waveform is as shown in the figure
below. (Focus gain adjustment)
100 mV
0 V
low focus gain
0 V
250 mV
high focus gain
VOLT/DIV: 100 mV
TIME/DIV:2ms
VOLT/DIV: 100 mV
TIME/DIV:2ms
VOLT/DIV: 100 mV
TIME/DIV:2ms
100 mV
75 mV
0 V
• Inconnect Examples (DC level changes more than on adjusted
waveform)
high tracking gain
high fandamental wave
than for low gain
VOLT/DIV: 1 V
TIME/DIV:2 ms
0 V
low tracking gain
VOLT/DIV: 1 V
TIME/DIV: 2ms
0 V
0 V
VOLT/DIV: 1 V
TIME/DIV: 2ms
8. Connect the oscilloscope to TP (TRACKING-Y) and TP (VC)
on the CD board.
9. Adjust RV704 so that the waveform is as shown in the figure
below. (tracking gain adjustment)
• Incorrect Examples (fundamental wave appears)
Note:
VOLT/DIV: with the 10:1 probe in used.
10. Release test mode after adjustment is completed.
Adjustment Location: CD board (See page 33.)